Fever is an important part of the body's defense against infection. Most bacteria and viruses that cause infections in people thrive best at 98.6°F. Many infants and children develop high fevers with mild viral illnesses. Although a fever signals that a battle might be going on in the body, the fever is fighting for, not against the person.

Brain damage from a fever generally will not occur unless the fever is over 107.6°F (42°C). Untreated fevers caused by infection will seldom go over 105°F unless the child is overdressed or trapped in a hot place.

Febrile seizures do occur in some children. Most febrile seizures are over quickly and do not mean your child has epilepsy. These seizures also do not cause any permanent harm.

Thrombophlebitis

Medications, such as some antibiotics, antihistamines, and seizure medicines

Home Care

A simple cold or other viral infection can sometimes cause a high fever (102 - 104°F, or 38.9 - 40°C). This does not usually mean you or your child has a serious problem. Some serious infections may not cause a fever, or may even cause a very low body temperature, especially in infants.

If the fever is mild and you have no other problems, you do not need treatment. Drink fluids and rest.

The illness is probably not serious if your child:

Is still interested in playing

Is eating and drinking well

Is alert and smiling at you

Has a normal skin color

Looks well when their temperature comes down

Take steps to lower a fever if you or your child is uncomfortable, vomiting, dried out (dehydrated), or not sleeping well. Remember, the goal is to lower, not eliminate, the fever.

When trying to lower a fever:

Do not bundle up someone who has the chills.

Remove excess clothing or blankets. The room should be comfortable, not too hot or cool. Try one layer of lightweight clothing, and one lightweight blanket for sleep. If the room is hot or stuffy, a fan may help.

A lukewarm bath or sponge bath may help cool someone with a fever. This is especially effective after medication is given -- otherwise the temperature might bounce right back up.

Do not use cold baths, ice, or alcohol rubs. These cool the skin, but often make the situation worse by causing shivering, which raises the core body temperature.

Here are some guidelines for taking medicine to lower a fever:

Acetaminophen (Tylenol) and ibuprofen (Advil, Motrin) help reduce fever in children and adults. Sometimes doctors advise you to use both types of medicine.

Take acetaminophen every 4 to 6 hours. It works by turning down the brain's thermostat.

Take ibuprofen every 6 to 8 hours. Do not use ibuprofen in children 6 months or younger.

Aspirin is very effective for treating fever in adults. Do not give aspirin to a child unless your child's doctor tells you to.

Know how much you or your child weighs, and then always check the instructions on the package to find the correct dose.

In children 3 months or younger, call your doctor first before giving medicines.

Eating and drinking:

Everyone, especially children, should drink plenty of fluids. Water, popsicles, soup, and gelatin are all good choices.

Do not give too much fruit juice or apple juice and avoid sports drinks in younger children.

Although eating is fine, do not force foods.

When to Contact a Medical Professional

Call a doctor right away if your child:

Is 3 months or younger and has a rectal temperature of 100.4°F (38°C) or higher

Is 3 to 12 months old and has a fever of 102.2°F (39°C) or higher

Is 2 years or younger and has a fever that lasts longer than 24 to 48 hours

Is older and has a fever for longer than 48 to 72 hours

Has a fever of 105°F (40.5°C) or higher, unless it comes down readily with treatment and the person is comfortable

Has other symptoms that suggest an illness may need to be treated, such as a sore throat, earache, or cough

Has had fevers come and go for up to a week or more, even if these fevers are not very high

Has a serious medical illness, such as a heart problem, sickle cell anemia, diabetes, or cystic fibrosis

Recently had an immunization

Has a new rash or bruises

Has pain with urination

Has trouble with the immune system (because of chronic steroid therapy, a bone marrow or organ transplant, spleen removal, HIV, or cancer treatment)

Has recently traveled to another country

Call 911 if you or your child has a fever and:

Is crying and cannot be calmed (children)

Cannot be awakened easily or at all

Seems confused

Cannot walk

Has difficulty breathing, even after the nose is cleared

Has blue lips, tongue, or nails

Has a very bad headache

Has a stiff neck

Refuses to move an arm or leg (children)

Has a seizure

Call your doctor right away if you are an adult and you:

Have a fever of 105°F (40.5°C) or higher, unless it comes down readily with treatment and you are comfortable

Have a fever that stays at or keeps rising above 103°F

Have a fever for longer than 48 to 72 hours

Have had fevers come and go for up to a week or more, even if they are not very high

Have a serious medical illness, such as a heart problem, sickle cell anemia, diabetes, cystic fibrosis, COPD, or other chronic lung problems